注意：未定义的偏移量：0 ... 25

$score = 0;
$topics = array();
for ($i = 0; $i < count($user_responses); $i++) {
    if ( ((int)$user_responses[$i]['response'])+((int)$mismatch_responses[$i]['response']) == 3 ){
        $score += 1;
        array_push($topics, $user_responses[$i]['topic_name']);
    }
}

It's appear

Notice: Undefined offset: 0

Notice: Undefined offset: 1

Notice: Undefined offset: 2

....

Notice: Undefined offset: 25

can anybody help me?

Thanks...

You can do two things in this case. Change the error reporting to 'E_ALL & ~E_NOTICE' so you won't be bothered with this messages. Or use the 'isset' function to check if a variable exists.

I think you problem lays here:

if ( ((int)$user_responses[$i]['response'])+((int)$mismatch_responses[$i]['response']) == 3 ){

you should first check if both variables exists, and use it if they do:

if (!isset($user_responses[$i]['response']) || !isset($mismatch_responses[$i]['response'])) continue; //skips the loop if one of the variables does not exist

if ( ((int)$user_responses[$i]['response'])+((int)$mismatch_responses[$i]['response']) == 3 ){